General
20 Chiller Air-cooled Screw
Delay Setting
Fig. 8
Delay Setting
Par. Setting
Alarm Display
Content
Temp Alarm
System Oil
Water Flow
System Pressure
Start Interval
Comp Start Delay
Comp Stop Delay
Fan Feedback
Contactor-feed
DP Delay
Comp Protect
Fan Stop Delay
30S
SET
SET
SET
15.0~60.0
0.3~1.5
0.3~5.0
90.0~350.0
0.5~1.5
1.0~30.0
10.0~900.0
1.0~20.0
0.0~900.0
8~15
20~200
60~200
3.0S
30.0S
9.0S
3.0S
10Min
30S
60S
2.0S
3.0S
300.0S
1.0S
The delay setting is composed of 3 screen cuts. In this display, control sequence delay and alarm determination delay
are configurable.
Start interval is delayed interval between consecutive starts. The delay is counted after the compressor is shut downed
and the next start is delayed for the elapse of the time. The startup delay is the delay between water pump run and com-
pressor run at startup phase. When the PLC receives start signal from operator, the PLC initiate the water pump firstly.
And after the defined delay, the PLC starts the compressor sequentially.
The outage delay is delay between minimization of the compressor capacity and compressor stop. When the PLC
receive stop signal from operator the PLC reset the capacity valves into minimum capacity position. And after the
defined delay, the PLC stop the compressor sequentially.
Oil preheat is startup delay of the chiller after receiving start signal. When the chiller is stopped preheating is performed
automatically. So through this delay, the preheating time is reserved.
The fan feedback delay is delay to check switch inputs from the magnetic contactors of the fans after energizing the
magnetic contactors. Similarly, the contactor feedback is delay to check switch inputs from the magnetic contactors of
the compressors after energizing the magnetic contactors.
DP means the delay for the determination of differential pressure alarm after the switch is opened. Comp protect is the
delay for the determination of compressor overload alarm by the internal protector of the compressor. Similarly, dis-
charge temp means the delay for the determination of high compressor discharge temperature alarm.
